The aim of this research was to investigate the seed quality of perennial ryegrass after 5-year storage treatments at various temperatures. The seeds of two cultivars of perennial ryegrass (diploid Bartwingo and tetraploid Calibra) were used, and the storage treatment temperatures were: room temperature (about 21°C), 10°C, -20°C and -80°C. Seed quality traits (germination and seedlings’ root and shoot lengths) were determined before and after the storage treatments. Additionally, early development traits in mini-pots during the first two months of development (emergence, plantlet height, plantlet root length, fresh weight of roots and shoots) were tested. The research has shown significant effects of storage temperatures to all the investigated traits of seed quality and plantlets development. The highest average values for germination and seedling root and shoot lengths were obtained after the storage at -80°C, and the lowest after storage at room temperature. The highest average values for emergence, plantlet height and roots and shoots fresh weights were obtained after the storage at -20°C, while the root length was greatest after the storage at -80°C. Tetraploid cultivar Calibra had significantly greater average values than diploid Bartwingo for all the investigated traits except for germination and primary shoot length.
Gordana Bukvić, Josip Juraj Strossmayer University of Osijek, Faculty of Agriculture in Osijek, Osijek, Croatia, email@example.com